In the construction of household refrigerators, there has been a continuing problem of reducing the amount of heat transferred through the relatively large refrigerator door and into the cooling compartment while maintaining a small door thickness.
It is known that heat pipes are useful in heating and cooling selected portions of a refrigerator, as taught by U.S. Pat. No. 2,537,314-Mortensen, which shows a heat pipe absorbing heat from the freezing compartment and dissipating the heat in a machinery compartment.
However, to provide a heat pipe system that would cool the door of a refrigerator presented a problem of how to construct the heat pipe system to provide for repeated opening and closing of the refrigerator door. Problems of lowered cooling efficiency and sweating of the apparatus are caused if the apparatus is constructed to pass from the cooling compartment into the door via a door hinge. A flexible connection coupling the heat pipe in the door with a heat pipe in the compartment was considered, but this construction was decided to be less durable than desired and would detrimentally affect the esthetic appearance of the refrigerator.
The construction of the door-cooling apparatus of this invention provides desirable cooling of the door while avoiding the problems of the previously considered structures.